I have installed a can light at the bottom of a dark stairwell to the existing light at the top operated by two 3 way switches (one down and one at the top) I strung the wire from the new can light to the switchbox at the bottom because it's the closest junction to the new light. I'm having trouble getting the new light to operate in tandem with both switches. At this point the bottom switch will turn on & off both fixtures from the bottom switch but the top switch only turns off the top fixture leaving the bottom one on.
I bought a basic wiring manual to try to clarify my dilema but, it doesn't exactly cover my predicament. Any guidance would be greatly appreciated.
PS I'm a forty year veteran flooring contractor. I'll be happy to answer any questions in that arena.

BigJimmy

04-18-2008 04:24 PM

Quote:

Originally Posted by dodleraspoon
(Post 117320)

I have installed a can light at the bottom of a dark stairwell to the existing light at the top operated by two 3 way switches (one down and one at the top) I strung the wire from the new can light to the switchbox at the bottom because it's the closest junction to the new light. I'm having trouble getting the new light to operate in tandem with both switches. At this point the bottom switch will turn on & off both fixtures from the bottom switch but the top switch only turns off the top fixture leaving the bottom one on.

I'm guessing that you have a 2/c cable coming to the box at the bottom and a 3/c cable running from the bottom to the box at the top of the stairs. In your case, the feed end of the circuit is likely at the bottom. 2 of the wires in the 3/c cable are being used as travellers and one (probably white) is being used as the neutral. You probably connected the new fixture at the bottom to the white wires and the other to a traveller position on the switch. Depending on the positions of the two switches, the lights would behave in the manner you described.

Unfortunately, unless I'm wrong and you actually have 2 separate 2/c cables running between boxes instead of a single 3/c, you're out of luck. You need and additional switch leg coming down from the top of the stairs to the lower box in order to wire both fixtures in parallel. If your electrical is installed in conduit however, you should be able to pull the additional wire with relative ease and rewire the circuit to make it work.

Let us know the details of what was existing and how you wired in the new fixture. A good picture or two is often very helpful.

Jim Port

04-18-2008 06:11 PM

It would be much easier wiring wise to run the wire from the fixture at the bottom of the stairs to the new recessed.

Depending on how the 3 ways are wired you may need to do this anyway.

220/221

04-18-2008 07:31 PM

Doh!

You (probably) need to run from the light or from the box with the switch leg in it.

Take a pic or describe in DETAIL how many and what kind of cables are in each switch box. There are many ways to wire a 3 way system. If the OTHER switch box has only one 3 wire cable, you can do it.

If you have a tester, you can figure it out.

On a 3ways switch there are 3 terminals. One is marked "common" and is darker than the others.

Put your tester on the common terminal and to ground. If you have power, flip the switch and check again. If you lose the power you are in the right box. That common terminal goes to your light. If you still have power, you are at the wrong end.

kjwoodworking

04-18-2008 10:00 PM

Quote:

Put your tester on the common terminal and to ground. If you have power, flip the switch and check again. If you lose the power you are in the right box. That common terminal goes to your light. If you still have power, you are at the wrong end.

220/221 is right about the switches. You need to get a wire from the switch that the dark screw loses power when switches are flipped or run wire from existing light that works correctly. Which ever is the least of a pain to do.

The switch that the dark screw has power if switches are flipped or not is the switch that is getting the power feed from the panel.

I worked in the industrial electrical field for 20 years before I was lucky enough to get into the relaxing world of woodworking. Don't miss it just glad I can do my own electrical when needed.

Hope this helps.

dodleraspoon

04-18-2008 10:15 PM

Cornfused

Thanks guys... I'm a tad less crosseyed.. I'll do my best to describe the wiring I see in the bottom switchbox. I assume the feed line (14-2) runs from the bottom box to the upper switch then to the existing light. I haven't looked behind the face plate.
IN the bottom switchbox are one (14-2) and one (14-3) existing as well as the feed line coming in from the breaker which is thankfully an arms lengh away. There's also another single pole switch for the garage light that's not part of this program other than it shares the box and the feed from the breaker. I ran the new (14-2) from the new recessed can light to this box figuring I could get away with only three holes in the sheetrock to patch. The exisitng 14-2 and 14-3 look to be going up to the top switch. the red wire is on the bottom left terminal, the black wire from the 14-3 is on the top left terminal and the black wire from the new 14-2 is on the bottom right terminal of the same bottom switch. The rest of the blacks are bundled together as are the white(neutrals)

kjwoodworking

04-19-2008 01:53 PM

dodleraspoon there is no telling how someone wired the switches. You see some crazy things in homes sometimes. It sounds lie it might be right though.

Here is a bad drawing of a three way switch wiring. I kept it simple by leaving out the neutral and ground wires. The neutral and ground just follow the hot wires to the light to give it a ground and the current a return path to the panel on the neutral.

power comes in on the black screw on one of the switches and then the black and red in the 14/3 alternate the current depending on how the switches are positioned to the other switch at the end of the hall or stairs.

The black screw on the other switch takes the power to the light.

A three way switch just alternates the current from the black screw to one of the brass screws as you flip a switch. Say the switch is up, then the power goes to one of the brass screws and then flip the switch down and it takes power away from that brass screw and makes the other one hot.

You need to get power to your new light from either the switch that feeds the light or from the existing light. Don't forget to connect the neutral and ground.